Process of preparing paper-coating composition



ngris a specification.

cases of tion. v 15 subject a action of a pebble grinding mill. In caseUNITED STAT S PATENT JOHN H. RYAN, OF CHICAGO, ILLINOIS.

"OFFICE.

raocrss. or PREPARING PAPER-COATING comrosrrron. I

no Drawin Application filed May 6, To all whom it may mam; e it knownthat I, JOHN H. RYaN,a c1t 1- zen of the United States, residing at.Chicago, "county oii,Cool and grovemen'ts in Processes of PreparingPaper 'oatin Com osition of which the follows application is acontinuation in part of my application for patent filed Sept. 22, 1919,Serial No. 325,467.

he invention relates to improved procpreparing paper coating composi-The object of the invention is to provide a p i. y fine and at a reducedcost.'

Objects relating to mere details will defi I nitely appear from thedetailed description ods which In carrying out my improved process, Iquantity of cl ay or whiting, to-the upon the doughy mass, distributethe pulverized grit, which may be-of a crystalline character throughoutthe colloidal mass in such a way that the crushed articles are separatedand any posslble rei rmation of in such a way that no grit ofconsiderable size can form anyhow. thin en this is done I'add sizingmaterial, sue as aproper solution ofcasem, glue or i hydrated starch,and the mixtureis "further sizin distribution of t ground therein untila complete blend of the has taken place with the thorough eminute gritthat have. been pulverizing. This last 1grindingconsumes usually aboutone-hal hour. The

grinding depends on the inirst period of of the material and-requirestial condition much longer. a n

ere casem' is employed In the siz ng Specification of Letters Patent.

paper coating of high grade quaht and reduce the same b ute same throughthe similar to that produced by 1 candy in the manufacture o uces a"comparable result,

smoothness of the coating mixture.

substantial equivalent of clay, clay being the broader description.

slightly different treatment;

. Having thus described further grmdingthe same .in a to insure mixtureand elimination of all grit,

2.. The position which consists in' first mixture of. water and acoating body, then adding sizing material including an alkalinecompound, and further ing mixture, substantially, as described.

Patented Feb. 28, 1922..

1920. Serial No. 379,315. v

of alkaline I as caustic soda, is added to may be the day he satin whiteand the added later. until all The mixit is pulver- By following themethods above outlined, compounds may be repared Fproducgrade qualitywithscreening of the mass here tofore found necessarv.

I have thus described specifically the methpursue, but desire to stateat this method'of treatment .may also be mass induced the action of thepebbles rolling through heavy mass: This induces an action ,the pulhngof insuring great In this behalf, I regard whiting as the Whitingrequires only my invention, what clalm as new and desire to secure byLetters Patent, is: I 1. The treatment of .clay consisting in mixing thesame with water until it is a hy mixture, subjecting the same to ofpebblesin a pebble grinding ddin'g the usual sizing-solutions, andpebble mill the pulverization and as specified.

preparing coating comgrinding a method of grinding the result- 3. Thetreatment of coating composition which vconsists inadding sufiicientWater to my hand and seal in'the presence of two forlm a goughy pasga'e,sugtlcting tile matei-1 wltnesses. v ria tot e antlon o a e e in in mi Ti to-pulverizethe grit th er ein a nd dist ibute 'JOHL RYAN i 5 the fineparticles through the colloidal mass, Witnesses:

as specified. LUELLA G. GREENFIELD, In witness whereof, I have hereuntoset MARGARET L. GLASGOW.

